In their recent commentary published in this journal, Hart et al. rightfully emphasized the importance of looking at new methods that would remove physical distancing measures and return to the new normal. ^{Reference Hart, Bortolin and Awoniyi1} The researchers concluded that multiple methods and public health guidelines have been proposed for public health preparedness, including the use of Immunity Cards/Passports. ^{Reference Hart, Bortolin and Awoniyi1} During pandemics such as coronavirus disease 2019 (COVID-19), disaster medicine and public health experts can help scientists, policy-makers, leaders, decision-makers, and the public in general to better understand the implications of using immunity passports and certificates. As with all public policy and interventions, safeguards are needed if vaccine passports are to be used by the public. ^{Reference Sleat, Innes and Parker2} This study contributes to the recent debate within the scientific community on the use of vaccine passports or certificates.

There is much debate about the use of “immunity passports” or COVID-19 Vaccine Certificate (CVC) in the context of COVID-19 pandemic. This “passport” would give people the rights and privileges that other members of the community do not have such as to work or travel. Immunity passports could allow those who have tested positive for antibodies to COVID-19 the freedom to return to work, shop, and travel. These passports could even be electronic and have a QR code that could be scanned like a boarding pass and presented as needed for entry to a variety of venues. The idea of an immunity passport is simple: have people carry a digital or physical proof that they have been infected with an infectious disease in the past and might, therefore, carry antibodies that make them immune, or that they have been immunized against such a disease.

An immunity passport would usually contain the identification details of the carrier and, where applicable, their vaccine-related information. Just as any document can be forged, so too is the potential for fraudulent immunity passports. To date, there is no consistent global standard or recommendation for immunity certificate exists at present. Nonetheless, the idea is being floated in the United States, Germany, the United Kingdom, and Southeast Asian nations. ^{Reference Zolfagharifard3} In the Philippines, several bills concerning the implementation of an immunity passport program have already been filed in the Congress and Senate. The aim of such bill is to provide persons who have received a COVID-19 vaccine certain benefits such as international or domestic travel, exemption from local checkpoints and quarantines, as well as access to business establishments.

Vaccine passports and certificates may have significant implications for privacy and autonomy, freedom, of movement and association, equity, and discrimination, particularly when it comes to accessing everyday goods and services. The World Health Organization (WHO) cautioned the public that vaccine passports should not be used at this time, particularly not as a prerequisite for travel “because of lack of vaccine equity.” ⁴ Proponents of immunity passport say it is a good way to jumpstart international travel and tourism, and eventually get back to our normal way of life. One justification for an immunity certification/passport is the key public health principle of least infringement. ^{Reference Childress, Faden and Gaare5} However, while the proposed immunity passport appears to be a useful tool to revive the global economy, immunity passports do carry scientific, ethical, and legal questions. Immunity passports, which can be viewed as a license card, are also an invitation for discrimination and fraud. First and most significant, there could be discrimination in the context of workplace. But protecting other employees from a nonimmune person who could catch and spread COVID-19 outweighs the ethical dilemma. In some settings, it may be justifiable to require workers to have been fully vaccinated against COVID-19. In the context of workplace, employers will look to hiring immune workers only. That may itself be discriminatory as able-bodied workers may be rejected. Another issue is that substantial numbers of workers would be unable to comply with a requirement to be vaccinated through no fault of their own such as those undergoing chemotherapy or with anaphylactic reactions to something in the vaccine. ^{Reference No-jab6} Third, there is the risk of socioeconomic discrimination. Immunity passport plans would likely disproportionately affect lower-income and minority groups. Vaccine passports have been seen as a way to restart economies to some, while others have criticized the documentation as creating further divide between wealthy nations and low-income countries that do not have widespread access to the vaccines. ^{Reference Corpuz7} In this context, the requirement of these immunity passports could, in practice, have a greater detrimental effect on the health of those working in certain industries and those with less income or savings. Fourth, there is a possible breach of data protection because these documents involve public health data and issues relating to proportionality and transparency. According to the Mandatory Reporting of Notifiable Diseases Law, persons who will be caught “falsifying, tampering, or using” counterfeit vaccination cards will have to pay a fine of 20,000 to 50,000 pesos and/or face imprisonment of 1 to 6 mo. ⁸ The crackdown is also in line with the recent move to restrict the mobility of unvaccinated persons and the implementation of “no vax, no ride policy” in Metro Manila. ^{Reference Caliwan9} Moreover, the system could quickly break down with rising cases, as those using forged or fake passports are not immune and are at risk of getting COVID-19.

In general, vaccine passports and certificates are more likely to be consistent with human rights when they are used as a tool to ease existing restrictions and improve public health outcomes. Rather than becoming a further requirement on top of the existing restrictions, vaccine passports and certificates should generally operate in place of them. The WHO cautioned the public regarding the implementation of immunity certification at present. The WHO states: “WHO’s position that national authorities and conveyance operators should not introduce requirements of proof of COVID-19 vaccination for international travel as a condition for departure or entry, given that there are still critical unknowns regarding the efficacy of vaccination in reducing transmission. In addition, considering that there is limited availability of vaccines, preferential vaccination of travelers could result in inadequate supplies of vaccines for priority populations considered at high risk of severe COVID-19 disease.” ^{Reference Zolfagharifard3} The use of immunity passports as part of the post-pandemic strategy should never be used as a main solution for a pandemic response. Moreover, if the scientific and ethical considerations above are met, then immunity passports could be used as part of the solution subject to a highly restrictive measures. These interventions should be evaluated by public health experts in the context of disaster medicine and public health preparedness.